Base64 Encoder
Encode text or files to Base64 locally in your browser.
Configuration
Click to upload or drag and drop
All files supported (Max: 5MB)
About Base64 Encoder
Convert text strings to standard Base64 or files to Data URL format. Uses UTF-8 encoding for full Unicode support. All processing runs locally in your browser with no server uploads.
How to use Base64 Encoder
- Select Text mode to encode a string or File mode to encode a file.
- In Text mode, type or paste the text you want to encode.
- In File mode, select the file you want to encode.
- Click the Run Tool button to perform the encoding.
- Review the Base64 output and size metrics in the results panel.
- Use the Copy button to copy the encoded output to your clipboard.
Best Practices
- Use Text mode for encoding string data like API payloads, configuration values, or tokens.
- Use File mode when you need a Data URL for embedding images or files inline.
- Be aware that Base64 output is approximately 33% larger than the original input.
- Do not use Base64 encoding as a security mechanism. Base64 is encoding, not encryption.
- If you only need the raw Base64 from file mode output, remove the data:<mime>;base64, prefix manually.
- Verify round-trip accuracy by decoding the output with the WebNift Base64 Decoder.
Benefits
- Encode text to standard Base64 with full Unicode and emoji support.
- Encode files to Data URL format including the MIME type header.
- Handle UTF-8 conversion automatically via the TextEncoder API.
- Process encoding locally in your browser with no data uploaded to any server.
- View original and encoded size metrics to understand the encoding overhead.
- Copy the encoded output directly to your clipboard.
Common Mistakes to Avoid
- Assuming Base64 encoding provides any form of data security or encryption.
- Forgetting that Base64 always increases data size by approximately 33%.
- Expecting URL-safe output. Standard Base64 uses +, /, and = which require additional encoding for URLs.
- Double-encoding data that is already Base64-encoded, producing a much larger string that must be decoded twice.
- Confusing File mode output (a Data URL) with raw Base64. File mode includes the data: prefix and MIME type.
Frequently Asked Questions
What is Base64 encoding?
Base64 is a method of representing binary data using 64 printable ASCII characters. It is used to carry binary content through text-only channels like JSON, email, and HTML.
Is Base64 encoding secure?
No. Base64 is a reversible encoding scheme, not encryption. Anyone can decode a Base64 string without a key or password.
Does this tool upload my data?
No. All encoding is performed locally in your browser using the TextEncoder and btoa() APIs. No data is sent to any server.
Why is the encoded output larger than my input?
Base64 represents every 3 input bytes as 4 output characters, resulting in approximately 33% size increase.
Does the encoder handle emoji and Unicode?
Yes. The encoder converts text to UTF-8 bytes via the TextEncoder API before encoding to Base64, which correctly handles all Unicode characters including emoji.
What is the difference between Text mode and File mode output?
Text mode produces a plain Base64 string. File mode produces a Data URL in the format data:<mime>;base64,<content>, which includes the MIME type of the uploaded file.
Does this tool support Base64URL?
No. This tool uses the standard Base64 alphabet with +, /, and = characters. Base64URL (using - and _) is not supported.
In-Depth Guide Available
Learn how to get the most out of Base64 Encoder with our step-by-step editorial tutorial.